Texas Instruments UCC28740EVM-525, Руководство пользователя

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SLUUAL8
TEST POINT NAME DESCRIPTION
TP4 SGND Secondary side ground
TP5 +VOUT Positive output terminal of the EVM to the load
TP6 -VOUT Return connection of the EVM output to the load
5.4 Applying Power to the EVM
1. Set up the EVM as shown in Figure 2 if testing at no-load, or Figure 3 if testing with a load.
2. If testing with a load, set the electronic load to constant resistance mode.
3. Set the AC source voltage between 85 V
AC
and 265 V
AC
.
4. Monitor the output voltage on DMM V
1
.
5. Monitor the output current on DMM A
1
.
5.5 No-Load Power Consumption
1. Use the test set up shown in Figure 2.
a. Set the power analyzer to external shunt mode.
b. Set the appropriate current scale factor for using an external shunt on the power analyzer.
A 10 Ω shunt scales to 10,000 mV/A for the PM100 Voltech.
c. Set the power analyzer for long averaging time to include several cycles of operation. The
PM100 Voltech used for this test data was set to a long averaging time of 30 for accurate
power consumption measurement.
2. Apply power to the EVM per section 5.4.
3. Monitor the input power on the power analyzer while varying thinput voltage.
4. Make sure the EVM is off and the bulk capacitors and output capacitors are completely
discharged before handling the EVM.
5.6 Line/Load Regulation and Efficiency Measurement Procedure
1. For load regulation, use the test set up shown in Figure 3.
a. Be sure to remove the exteranal 10 Ω shunt from the power analyzer and set the analyzer
to normal mode (not long averaging).
b. Set the AC source to a constant voltage between 85 V
AC
and 265 V
AC
.
c. Vary the load so that the output current varies from 0 A up to 2.1 A, as measured on DMM
A
1
.
d. Observe that the output voltage on DMM V
1
remains within 3% of the 5 V constant voltage
regulation value.